Tight Binding

Construction of two-center tight-binding Hamiltonians

GTTbHamiltonian — constructs the tight-binding Hamiltonian in k-space from the information about basis and lattice.

GTTbHamiltonianElement — constructs an element of the tight-binding Hamiltonian.

GTTbMatrixElement — expresses tight-binding matrix element in two-center form.

GTTbSpinMatrix — gives the elementary spin matrices for tight-binding Hamiltonians.

GTTbSpinOrbit — adds spin-orbit coupling to a given tight-binding Hamiltonian.

GTTbSymbol2C — gives a symbol according to the nomenclature of the two-center approximation.

GTTbHamiltonianOnsite — corrects onsite energies with respect to crystal field splitting

Construction of three-center tight-binding Hamiltonians

GTIrepInfo — information about selected irreducible representations.

GTSymmetryBasisFunctions — calculates to which irreducible representations the wave functions are basis functions.

GTTbNumberOfIntegrals — calculates the number of independent tight-binding integrals for functions transforming like irreducible representations of point group.

GTTbMatrixElement3C — calculates matrix element of three-center Hamiltonian

GTTbSymbol3C — Symbols in three-center form

GTTbIntegralRules — rules to find independent parameter

GTTbVarList — prepare list for parameter substitution

Tight-Binding Real Space Formulation

GTFindStateNumbers — finds the number of states lying in a certain energy interval.

GTPlotStateWeights — demonstrates at which atoms of a cluster, the wave function has the highest weights.

GTTbHamiltonianRS — constructs a tight-binding Hamiltonian in real space.

GTTbRealSpaceMatrix — constructs the interaction of two atoms in a real space tight-binding Hamiltonian.

Parameter sets and libraries for tight-binding models

GTTbDatabaseInfo — gives information about the tight-binding parameter sets available in database.

GTTbDatabaseRetrieve — loads a tight-binding parameter set.

GTTbDatabaseUpdate — reads, updates and stores tight-binding parameter sets.

GTTbGetParameter — gives the value of a parameter from a tight-binding parameter set.

GTTbParameterNames — creates a set of parameter names.

GTTbParmToRule — gives a rule to replace tight-binding symbols.

GTTbPrintParmSet — prints a tight-binding parameter set.

Wave functions

GTTbAtomicWaveFunction — constructs an atomic-like wave function.

Symmetry Analysis of Band Structures

GTTbSymmetrySingleBand — symmetry analysis of a single band at a certain k-point.

GTTbSymmetryPoint — symmetry analysis of the TB band structure at a certain k-point.

GTTbSymmetryBands — symmetry analysis of the entire TB band structure.

Output of Hamiltonians as FORTRAN Modules

GTTbToFortran — transforms a k-space tight-binding Hamiltonian into a FORTRAN module.

GTTbToFortranList — prints a Hamiltonian as FORTRAN code.

Nanotubes

GTTbTubeBands— calculates bands for a nanotube

Wannier90

GTTbReadWannier90— reads information from the WANNIER90 package.

GTTbWannier90Hamiltonian— constructs Hamiltonian from WANNIER90 output.

Miscellaneous

GTHamiltonianPlot — plots the structure of a Hamiltonian.

GTHamiltonianList — list of elements of a tight-binding Hamiltonian